The Dexter Tunnel is a gold and silver mine located in Rio Grande county, Colorado at an elevation of 11,608 feet.
About the MRDS Data:
All mine locations were obtained from the USGS Mineral Resources Data System. The locations and other information in this database have not been verified for accuracy. It should be assumed that all mines are on private property.
Mine Info
Elevation: 11,608 Feet (3,538 Meters)
Commodity: Gold, Silver
Lat, Long: 37.42583, -106.59639
Map: View on Google Maps
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Dexter Tunnel MRDS details
Site Name
Primary: Dexter Tunnel
Secondary: Claim: Dexter
Secondary: Ms 77
Commodity
Primary: Gold
Primary: Silver
Secondary: Copper
Location
State: Colorado
County: Rio Grande
District: Summit (Summitville) District
Land Status
Land ownership: Private
Note: the land ownership field only identifies whether the area the mine is in is generally on public lands like Forest Service or BLM land, or if it is in an area that is generally private property. It does not definitively identify property status, nor does it indicate claim status or whether an area is open to prospecting. Always respect private property.
Holdings
Not available
Workings
Type: Surface/Underground
Ownership
Not available
Production
Not available
Deposit
Record Type: Site
Operation Category: Past Producer
Operation Type: Unknown
Discovery Year: 1873
Discovery Method: Ore-Mineral In Place
Years of Production:
Organization:
Significant: N
Deposit Size: S
Physiography
General Physiographic Area: Rocky Mountain System
Physiographic Province: Southern Rocky Mountains
Mineral Deposit Model
Model Name: Polymetallic veins
Orebody
Not available
Structure
Type: R
Description: San Juan Volcanic Field
Type: L
Description: Platoro Caldera, Summitville Caldera, Summitville Fault, South Mountain Dome
Alterations
Alteration Type: L
Alteration Text: Quartz-Alunite Solfataric Alteration
Rocks
Name: Quartz Latite
Role: Associated
Age Type: Host Rock
Age Young: Miocene
Name: Quartz Latite
Role: Associated
Age Type: Associated Rock
Age Young: Miocene
Analytical Data
Not available
Materials
Not available
Comments
Comment (Location): ON NE SLOPE OF SOUTH MTN 1600 FT SE OF CHANDLER PORTAL. PORTAL ELEV FROM STEVEN AND RATTE (1960, PL. 4). ; INFO FROM LAND.ST :1975
Comment (Deposit): MINE DEVELOPED ON DEXTER (ODIN) VEIN, ONLY SIGNIFICANT VEIN IS DISTRICT TRENDING EAST-WEST. AT SURFACE, BODIES OF VUGGY QUARTZ ROCK IN QUARTZ-ALUNITE ZONE APPEAR TO BE DISCONTINUOUS, BUT TREND IS WELL DEFINEDIN DEXTER AND FRENCH LEVELS. OTHER VEIN ZONE OF COMPACT QUARTZ AND VUGGY QUARTZ ROCK PROJECTS SOUTH FROM DEXTER VEIN AND IS CALLED QUEEN OR HIGHLAND MARY VEIN. NW PROJECTIONS FROM DEXTER VEIN REFERRED TO AS PITTSBURGH AND QUEEN VEINS.
Comment (Workings): TUNNEL DRIVEN GENERALLY DUE WEST FOR 1120 FT ALONG DEXTER VEIN TO LITTLE ANNIE VEIN AND APPARENTLY JOINING WITH WORKINGS OF IDA TUNNEL. QUEEN OPEN CUT ON SURFACE ABOVE TUNNEL.
References
Reference (Deposit): PATTON, H.B., 1917, GEOLOGY AND ORE DEPOSITS OF THE PLATORO-SUMMITVILLE MINING DISTRICT, COLORADO: CGS BULL. 13.
Reference (Deposit): STEVEN, T.A., AND RATTE, J.C., 1960, GEOLOGY AND ORE DEPOSITS OF THE SUMMITVILLE DISTRICT, SAN JUAN MOUNTAINS, COLORADO: USGS PROF. PAPER 343
Reference (Deposit): LIPMAN, P.W., 1974, GEOLOGIC MAP OF THE PLATORO CALDERA AREA, SOUTHEASTERN SAN JUAN MOUNTAINS, SOUTHWESTERN COLORADO: USGS MAP I-828.
Reference (Deposit): BLM MINERAL SURVEY MS 77
Colorado Mining Photos
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